RESUMEN
PURPOSE: To develop an instrument that measures empowerment among people with a long-term work disability. METHODS: A six-dimension empowerment model was chosen as a theoretical framework. These dimensions are as follows: competence, self-determination, meaning, impact, positive identity and group orientation. A literature search was conducted to find instruments that currently are being used to measure one or more of these constructs. Validated and applicable instruments from this search were used in a preliminary questionnaire. A pilot test was conducted consulting the target population and experts. On basis of changes from this pilot, a concept questionnaire was conducted. In a field test, this questionnaire was sent to 976 subjects who followed a vocational rehabilitation course in the years 2001-2003. Item-total correlations and factor analyses were performed on the collected data to reduce the number of items. Factor analysis was performed, and internal consistency was determined to get insight into the psychometric properties of the final questionnaire. RESULTS: From all subjects who were approached, 385 (39%) returned usable questionnaires that could be analysed. Item reduction by item-total correlations and factor analysis resulted in a final questionnaire consisting of 62 items divided over the six subscales. Internal consistency of the subscales was good: all subscales had Cronbach's alphas between 0.80 and 0.91. Some inter-correlation existed between the subscales competence, self-determination and impact. CONCLUSIONS: The 'VrijBaan' questionnaire was developed to measure empowerment among people with a long-term work disability. Although the results support the internal consistency of the subscales, further psychometric work is needed to improve the quality of this questionnaire.